Apparatus for pyrogenically recording on transparencies



Nov. 25, 1969 R. c. zoPPofH ET AL 3,480,965

APPARATUS FOR PYROGENICALLY RECORDING ON TRANSPARENCIES Filed April 15, 1968 w l l I INVENTORB 2 RAYMOND C. ZOPPOTH JAMES E. YOUNG United States Patent 3,480,965 APPARATUS FOR PYROGENICALLY RECORDING ON TRANSPARENCIES Raymond Carl Zoppoth, Rochester, and James E. Young,

Pittsford, N .Y., assignors to Xerox Corporation, Rochester, N.Y., a corporation of New York Filed Apr. 15, 1968, Ser. No. 721,332 Int. Cl. G01d /10 US. Cl. 34676 7 Claims ABSTRACT OF THE DISCLOSURE Apparatus for recording information onto transparencies in which a transparency is masked to expose selected areas thereon according to a desired pattern of information and subjected to high intensity electromagnetic radiations to pyrogenically alter the optical characteristics in the exposed areas.

BACKGROUND OF THE INVENTION This invention relates generally to method and apparatus for recording identifying information onto transparencies and the like and more particularly to method and apparatus for recording identifying information onto transparencies having images thereon which have been photographically produced.

In many applications it is often desirable to add additional information such as titling, coding, numbering, etc. to photographic film after an image has been photographically reproduced thereon. In the past, mechanical methods for adding information have included stamping the film with printing characters as the film is transported past a printing station on a conveyor transport. Although this method has proven elfective in some respects for adding information to processed film, this technique has nevertheless not been widely utilized due to the fact that it is time consuming, requires laborious adjustments to obtain marking of a desirable quality and subje'cts the film material to an unnecessary high probability of damage.

Another approach to recording identifying information on photographic film has been to expose the film to superimposed identifying information simultaneously with the initial exposure. Subsequent processing therefore produces both the original subject matter and its identifying information simultaneously. However, this approach has the inherent disadvantage of not being able to add additional information after the raw film stock has been processed.

Techniques for adding additional information after processing by other than mechanical means have also been employed. One such method includes coating the emulsion in the marking areas with a protective coating such as paraffin and impressing photoengraved dies containing the information onto the coating. This displaces the coating and exposes the emulsion in image configuration. Thereafter the emulsion is removed by allowing an etching agent such as sodium hypochlorite to act upon the exposed parts of the emulsion. However, this approach has the disadvantage of being expensive and time consuming in that additional processing is required.

Another approach has been the utilization of the now well known xerographic process. One such technique is disclosed in Carlson patent US. 2,297,691 in which a powder image of a thermoplastic resin is applied and fused to the film in the marking areas. Although the xerographic process has provided an effective method for adding identifying information to photographic film it nevertheless has required additional complex apparatus in accomplishing the intended result.

Patented Nov. 25, 1969 SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to record identifying information on transparencies such as photographic film and the like.

It is another object of the present invention to record identifying information on transparencies such as photographic film and the like by changing the optical characteristics of the transparency in an information configuration.

It is a further object of the present invention to provide an efiicient and inexpensive method for recording information onto transparencies such as photographic film and the like by pyrogenically altering the optical characteristics of the transparency.

-It is still a further object of the present invention to provide apparatus for recording information onto transparencies such as photographic film and the like in which the optical characteristics of the transparency are pyrogenically altered according to an information configuration.

These and other objects of the invention are attained by subjecting a transparency on which information is to be recorded to a potential source of high intensity electromagnetic radiation, masking the transparency to expose selected areas thereon to radiations emitted by the source, and activating the source of electromagnetic radiation for a predetermined time period of pyrogenically alter the optical characteristics of the transparency in the exposed areas.

Other objects of the invention will become readily apparent to those skilled in the art in view of the following detailed disclosure and description thereof, especially when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a perspective view illustrating a specific embodiment of apparatus for recording as contemplated by the present invention.

FIGURE 2 is a schematic cross sectional view of a specific embodiment of apparatus for recording as contemplated by the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGURE 1, a transparency such as photographic film and the like onto which idenitfying information is to be recorded is subjected to a potential source of high intensity electromagnetic radiation. Transparency 10 may comprise any suitable material, such material including cellulose triacetate, ester, or cellulose acetate 'butyrate. In the schematic illustrations of FIGURES 1 and '2, photographic film is shown by way of example as a typical transparency onto which information is to be recorded. However, the specific reference to photographic films is by way of illustration only and should not in any sense be interpreted as limited to such transparencies.

As may be seen from FIGURE 1, transparency 10 comprises a base layer 12 with a suitable photographic emulsion 14 coated thereon. Such coatings may include silver halide emulsions which are commonly utilized in photographic films. Where the transparency onto which informatio is to be recorded comprises a photographic film, it is generally desirable to record the information in the image areas along one edge of the film or adjacent to the sprocket holes, if a film having such sprocket holes is utilized. It should be understood, however, that the recorded information need not be placed in the emulsion areas but may be. placed elsewhere on the transparency.

The source of electromagnetic radiation may comprise a flash lamp such as 15. Typical flash lamps which are commercially available and provide suitable sources of electromagnetic radiations are filled with a gas such as xenon, argon, mercury, or mixtures thereof and are capable of emitting radiation output of wavelengths in the range of 2,000 to 24,000 angstroms. In practice, a xenon flash lamp has been found to work particularly well. Normal pulse widths for such lamps are on the order of from 100 microseconds to 2 milliseconds which provide a desirably high repetition discharge rate. Operating voltages suitable for this purpose range on the order of about 800 volts to about 2500 volts. The spectral response of such lamps start at about 2,000 angstroms and extend to about 18,000 angstroms peaking in the short infrared range or at about 8,000 angstroms.

The particular lamp 15 illustrated may comprise a gas filled quartz tube containing two electrodes 16 and 17, one sealed at each end thereof. The lamp 15 is energizer.

by a trigger coil 18 encircling the quartz tube intermediate the two electrodes. Trigger coil 18 is coupled to a trigger circuit (not shown) such as a simple relay circuit or controlled rectifier circuit, which when activated provides a suitable high voltage .pulse to the trigger coil 18. This pulse through the coil 18 generates a high magnetic field in the lamp thereby causing ionization of the gas within, between electrodes 16 and 17 to which is applied a potential.

The potential applied to electrodes 16 and 17 may be obtained from a suitable power source, rectified, and transformed to the desired operating voltage. A capacitor in the power supply circuitry is charged to an initial potential dependent upon the parameters of the circuit, prior to ionization of the gas Within lamp 15. Upon ionization, the lamp presents a low impedance across the electrodes 16 and 17 thereby striking a conductive arc discharging the capacitor. After discharge of the capacitor, the gas lamp 15 de-ionizes allowing a charge to be stored again in the capacitor. A switch is included in the trigger circuit for activating the flash lamp 15 according to a programmed or selected sequence.

Flash lamp 15 is enclosed in a housing 20 comprising a reflector portion 21 and a base portion 22. Housing 20 directs radiations emitted by the flash lamp 15 onto the transparency passing through mask 30. An aperture 23 in base portion 22 encloses the housing 20 in all but a selected area to permit concentration of the elec tromagnetic radiations from flash lamp onto a localized area of the underlying transparency.

A mask 30 of the identifying information which is to be recorded onto the transparency, is interposed between the flash lamp 15 and the exposed area of the underlying transparency 10. The information to be recorded may include alphanumerics as well as various patterns of coded information. The mask 30 is interposed between flash lamp 15 and the underlying transparency 10 to expose the transparency 10 in selected areas to radiations emitted by flash lamp 15 and to shield the transparency in selected areas from radiations emitted by the flash lamp 15, the exposed areas representing the particular pattern of identifying information which is to be recorded thereon.

Upon activation of the flash lamp 15, radiations are absorbed by the transparency in the exposed areas. The flash lamp 15 is energized for a predetermined time period and at a controlled intensity to produce a heating thereof, the heating being suflicient to alter the optical characteristics of the transparency in the exposed areas.

Where the transparency being utilized is in the nature of photographic films, and the information is recorded onto the emulsion areas, the heating therein produces an emulsion deformation, the degree of which may be controlled by varying the intensity and the time duration of exposure. The deformation produced thereby may be controlled, varying from a Slight burnishing of the emulsion, up to pyric decomposition in the exposed areas. Ideally, however, the deformation should be limited to a slight burnishing or frosting of the emulsion to assure permanence and legibility without obtaining serious alteration of the film characteristics.

After recording the information onto the film, projection of the images will successfully show the information thereon since the light transmission characteristics of the film have been altered in the exposed areas. Thereafter, this information may be reproduced on transparencies which are produced from the original, since density in the exposed areas has been altered by the recording process.

Various techniques may be utilized to mask the transparency according to the desired pattern of information to be recorded. For example, stencils or masks 30 in the form of webs or tapes may be prepared in a pattern of coded information, alphanumerics or combinations thereof. These stencils or masks are then interpositioned between the transparency and the source of electromagnetic radiation which when energized exposes the transparency 10 according to the particular information configuration.

The stencils or masks 30 are preferably formed from a material which is reflective to the particular range of Wavelengths emitted by the source being utilized. This ensures deformation of the transparency 10 in the exposed areas only and reduces the possibility of film damage by conductive heating in the non-image areas. Such stencils or masks may be readily prepared by known tape punching or stencil making techniques simultaneously with viewing of a particular transparency by a transparency interpreter. Thereafter, the mask or stencil thus produced may be utilized in an apparatus such as that disclosed in FIGURE 2, and the information recorded onto the transparency.

Instead of utilizing tapes or webs for masking the transparencies, an alternative may be to utilize a character generator system for recording information onto the transparency, character by character. One known character generator system which is particularly adapted for use in connection with the instant recording process is of the type which employs a reflective disk having transparent characters distributed thereabout. Such character generator systems may be tape programmed to pulse the flash lamp 15 in accordance with the particular information to be recorded whereby the information is recorded onto the transparency, character by character, in the manner as described.

Referring to FIGURE 2, there is schematically illustrated one embodiment of apparatus for recording information onto a transparency as contemplated by the present invention. As shown therein, a photographic film transparency 10 in the form of a continuous Web is supported on a supply reel 11 and transported to a takeup reel 13 by means of drive motor 33. Film web 10 passes from supply reel 11 over a first idler roll 24 then over a support platen 26, then over a second idler roll 25 and wound onto takeup reel 13.

A prepared stencil or mask 30 in the form of a tape is supported on supply reel 27 and is transported to takeup reel 28 by means of drive motor 34. Drive motor 33 and 34 may be programmed to either operate in synchronism or independently of each other. Tape 30 passes from supply reel 27 over a first idler roll 31 where it is pressed into operative relationship with the transparency 10 positioned on support platen 26, then over a second idler roll 32, which aids idler roll 31 in pressing tape 30 into operative relationship with transparency 10 and then is wound onto takeup reel 28.

Reflector housing 20 which supports flash lamp 15 therein is supported intermediate idler rolls 31 and 32 to direct radiations emitted by flash lamp 15 through perforations in tape 30 and onto film strip 10. Thus, as flash lamp 15 is energized, film strip 10 will be heated thereby in the exposed areas, thus deforming the trans parency according to the exposed configuration. Film strip and tape may thereafter be advanced respectively by motors 33 and 34 to bring successive areas therealong into operative position above platen 26 to receive radiations emitted by flash lamp 15.

From the foregoing description it may be readily seen that there is provided an efiicient and inexpensive yet simple method for recording information onto transparencies such as photographic film and the like.

While the invention has been described with reference to its preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the true spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teaching of the invention without departing from its essential teachings.

What is claimed is:

1. Apparatus for recording identifying information onto transparencies such as photographic film and the like comprising,

a source of high intensity electromagnetic radiation,

means for supporting a transparency onto which information is to be recorded proximate to said source of radiation, means for directing radiations emitted by said source toward said transparency, means interposed between said transparency and said source for masking said transparency to expose selected areas thereof to radiations emitted by said source, said masking means being formed from a material which is reflective to the radiations emitted by said source, the exposed areas representing patterns of the information to be recorded, and means for energizing said source for a predetermined time period at a predetermined intensity, said predetermined time period and said predetermined intensity being of suflicient duration and magnitude to pyrogenically alter the optical characteristics of the transparency in the exposed areas. 2. Apparatus according to claim 1 wherein said source of high intensity electromagnetic radiation is enclosed in a housing comprising reflector and base portions, said comprising a continuous web of flexible material and further including,

means for advancing said web in relation to said source to bring different areas therealong into operative relationship with said transparency.

5. Apparatus according to claim 1 wherein said source of high intensity electromagnetic radiation is a xenon flash lamp.

6. Apparatus according to claim 5 wherein the radiation generated by said xenon flash lamp is characterized by a flash time duration from about 100 microseconds to 2 milliseconds and an emission of radiation from about 2,000 angstroms to about 18,000 angstroms.

7. Apparatus according to claim 6 wherein the characteristics of the transparency in the non-exposed areas are not altered by the exposure of said transparency to said radiation.

References Cited UNITED STATES PATENTS 3,038,994 6/1962 Nelson et al 250- 3,111,584 11/1963 Appledorn 250-65 3,135,621 6/1964 Damm et a1 34676 X 3,158,432 11/1964 Arend et a1. 346108 3,266,393 8/1966 Chitayat 1.1

FOREIGN PATENTS 1,005,463 9/ 1965 Great Britain.

JOSEPH W. HARTARY, Primary Examiner U.S. Cl. X.R. 951.1; 25065 

